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Subject: Re: [PATCH] mm: mempolicy: use VM_BUG_ON_VMA in
 queue_pages_test_walk()
To:     Qian Cai <cai@lca.pw>
Cc:     akpm@linux-foundation.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
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 <1221B3C6-6A3B-4427-92DD-25AD54FF6BB5@lca.pw>
From:   Yang Shi <yang.shi@linux.alibaba.com>
Message-ID: <d6c1a434-8670-97f4-345c-28c8007a25ce@linux.alibaba.com>
Date:   Mon, 27 Jan 2020 11:57:17 -0800
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On 1/27/20 10:17 AM, Qian Cai wrote:
>
>> On Jan 15, 2020, at 1:09 AM, Yang Shi <yang.shi@linux.alibaba.com> wrote:
>>
>> The VM_BUG_ON() is already used by queue_pages_test_walk(), it sounds
>> better to dump more debug information by using VM_BUG_ON_VMA() to help
>> debugging.
> What’s the problem this is trying to resolve? Was there an existing bug would trigger this?

Dumping more information to help debugging. I don't run into related bug 
personally.